Method of producing a plated product having recesses

ABSTRACT

A plated product and apparatus for forming recesses or grooves on material to be plated to produce such a product. The product includes material having a surface having many recesses, each having an opening of size d, where d is in the range 5-100 microns, a depth in the range from 0.2 d to d, or many grooves. In preferred embodiments, each groove or recess has an anchor portion. In some embodiments, each groove has a ridge portion at each of both edges of its opening. The angle of each groove to the surface of the material and each groove&#39;s depth and opening width are preferably in specified ranges. When the material is plated, part of the thin metal film enters the anchor portions of its grooves or recesses, so that the plated metal has superior capacity to resist peeling off of the plated metal.

BACKGROUND OF INVENTION

1. Field of Invention

This invention relates to a plated product in which the surface of ametallic or nonmetallic material is plated, and to a method andapparatus for producing it.

2. Prior Art

When the surface of a metallic or nonmetallic material is to be plated,it has been conventionally attempted to form fine recesses on thematerial before plating it, so as to enhance the adhesion of thematerial with a thin film of metal (plating). To form the recesses,various methods have been proposed. For example, in a certain method,fine powder particles are caused to hit the material. In another method,a certain kind of substance or fine particles that are dissolvable in aspecified solution are previously embedded near the surface of thematerial, or mixed with the material, and the substance or fineparticles are then dissolved in the solution.

In the former method, the sizes of the fine powder particles range fromseveral tens to several hundreds of μm. Therefore, the fine recesses areformed by plastic deformation or a cutting force resulting from thecollisions of the powder particles with the material to be plated. FIG.1 (a) shows a recess mainly formed by the plastic deformation made bythe powder particles hitting the surface of the material atsubstantially right angles to it. FIG. 1 (b) shows a recess mainlyformed by the cutting force formed by the powder particles hitting thesurface of the material at an acute angle of incidence to the surface.Each of these recesses has a form that opens outwards, like a stateafter a meteorite has collided with a planet. Therefore, when thesurface of the material is plated, the adhesion of the thin film ofmetal to the surface depends on the thin film of metal's own adhesiveforce, the resistance due to the uneven surface of the material, and thearea of adhesion. Therefore, the following problems have occurred:

When a force is applied in a direction substantially parallel to thesurface of the material, not only the thin film of metal's own adhesiveforce, but also a resistant force (peeling resistance) is generated, inresponse to the resistance due to the uneven surface of the material,and to the size of the area where the metal adheres to the surface ofthe material to be plated. When a force is applied at substantiallyright angles to the surface of the material, the adhesion of the thinfilm of metal to the surface of the material depends only on theadhesion force of the thin film of metal, and the resistance due to theuneven surface of the material and the size of the adhered area do notcontribute to the retention of the thin film of metal on the surface ofthe material. Thus, when a mechanically great force such as a stronghitting force is applied to a part of the plated surface, a phenomenonof fine peeling occurs on that part of the plating. Further, if theforce is repeated, then the peeling increases, so that the thin film ofmetal peels off the material.

In the latter method, the sizes of the fine recesses on the surface ofthe material depend on the sizes of the substance or the particlesembedded or mixed. The sizes of the fine recesses are less than 2˜3 μm.As in FIG. 2 (a), the size of the opening of a recess is small ascompared with the size of the entire recess. Therefore, in plating amaterial, the metal tends not to enter the recess. FIG. 2 (b) shows thatthe thin film of metal only blocks the opening of the recess. This leadsto the adhesion of the thin film of metal to the surface of the materialdepending only on the thin film of metal's own adhesive force. Thus,when a mechanically large force is applied to the plated material, andis applied to a particular point on its surface, at right angles, thethin film of metal at that point peels off the material.

SUMMARY OF INVENTION

This invention has been created to resolve the above problems.Therefore, one object of this invention is to provide a plated productin which the thin film of metal tends not to peel off the surface of thematerial, and a method and apparatus for producing it.

Another object of this invention is to provide a plated product in whichthe surface of a metallic or nonmetallic material is plated, thatcomprises a material of which the surface has many recesses, each havingan opening of 5˜100 μm and a depth of 0.2 d˜d (d: the diameter of theopening of a recess, μm), and having an anchor portion, and a thin filmof metal which covers the surface of said material and a portion ofwhich film enters each said recess.

Another object of this invention is to provide a method of producing aplated product in which the surface of a metallic or nonmetallicmaterial is plated, that comprises causing the top of a needle or adrawn wire material of a diameter of 3˜95 μm to penetrate said surfaceof said material at angles of less than 90 degrees, but more than 45degrees, withdrawing said needle or said drawn wire material from saidmaterial and repeating this process so as to provide at said surface ofsaid material many recesses, each having an opening of 5˜100 μm and adepth of 0.2 d˜d (d: the size of the opening of a recess, μm) and havingan anchor portion, and covering said surface of said material thatincludes said recesses with a thin film of metal.

A further object of this invention is to provide an apparatus forproducing a plated product in which the surface of a metallic ornonmetallic material is plated, that comprises a needle or a drawn wirematerial of a diameter of 3˜95 μm, a retainer means for retaining thebase portion of said needle or said drawn wire material so that saidneedle or drawn wire material is inclined at angles larger than 45degrees, but less than 90 degrees, to said surface of said material, amaterial-fixing means to fix the material, and a means for elevating orlowering said retainer means.

Still another object of this invention is to provide a plated product inwhich the surface of a metallic or nonmetallic material is plated,characterized by a plurality of grooves formed on the surface of saidmaterial, the width of the opening of each groove being 5˜100 μm and thedepth of each groove being 0.2 b˜b (b: said width of the opening, μm),and the angle of each said groove to the surface of said material beingwithin a range of more than 45 degrees, but less than 90 degrees.

A still further object of this invention is to provide a method ofproducing a plated product in which the surface of a metallic ornonmetallic material is plated, comprising causing a cutting bladehaving a thickness of 3˜95 μm to penetrate said surface of said materialwhile said cutting blade is inclined to said surface of said material atangles within a range of more than 45 degrees, but less than 90 degrees,moving said cutting blade or said material to cause them to moverelative to each other and repeating this process so as to provide atsaid surface of said material a plurality of grooves, many running indifferent directions, the width of the opening of each groove being5˜100 μm and the depth of each groove being 0.2 b˜b (b: said width ofthe opening, μm), and covering said surface of said material thatincludes said grooves with a thin film of metal.

Still another object of this invention is to provide an apparatus forforming a plurality of grooves on the surface of a nonmetallic ormetallic material for a plated product, comprising a retainer means forretaining the base portion of said cutting blade having a thickness of3˜95 μm so that said cutting blade is inclined to said surface of saidmaterial at angles within a range of more than 45 degrees, but less than90 degrees, a material-fixing means to fix said material, a means forelevating or lowering said retainer, a first moving means to move saidretainer means in the direction that the blade of said cutting blade isdirected, and a second moving means to move said material-fixing meanshorizontally.

A still further object of this invention is to provide a plated productin which the surface of a metallic or nonmetallic material is plated,characterized by many grooves formed on the surface of said material,the width of the opening of each groove being 5˜100 μm and the depth ofeach groove being 10˜90% of the thickness T of a plated layer, the angleof each said groove to the surface of said material being within a rangeof more than 30 degrees, but less than 150 degrees, and each groovebeing provided at each of both edges of its opening with a ridge portionwhose height is 10˜90% of said thickness T of said plated layer.

Still another object of this invention is to provide a method ofproducing a plated product in which the surface of a metallic ornonmetallic material is plated, comprising causing a, cutting bladehaving a thickness of 3˜95 μm to be pressed on said surface of saidmaterial while said cutting blade is inclined to said surface of saidmaterial at angles within a range of more than 30 degrees, but less than150 degrees, and moving said cutting blade or said material to causethem to move relative to each other, and repeating this process so as toprovide at said surface of said material many grooves, many running indifferent directions, the width of the opening of each groove being5˜100 μm, and the depth of each groove being 10˜90% of the thickness Tof a plated layer or 2˜18 μm, and to provide ridge portions, the heightof each of which is 10˜90% of the thickness T of a plated layer or 2˜18μm, and covering said surface of said material that includes saidgrooves and ridge portions by metal plating.

A still further object of this invention is to provide, in producing aplated product in which the surface of a metallic or nonmetallicmaterial is plated, an apparatus for forming grooves and their ridgeportions on the surface of said material comprising a retainer means forretaining a cutting blade having a thickness of 3˜95 μm so that theblade surface of said cutting blade is inclined to said surface of saidmaterial at angles within a range of more than 30 degrees, but less than150 degrees, a material-fixing means to fix said material, a means forelevating or lowering said retainer means, a first moving means to movesaid retainer means in the direction in which the blade of said cuttingblade is directed, and a second moving means to move saidmaterial-fixing means horizontally.

This invention provides a plated product comprising a material of whichthe surface has many recesses or grooves that have anchor portions. Apart of a plating metal enters the recesses or grooves. Also, eachgroove can be provided with a ridge portion at each of both edges of theopening of each groove. Therefore, the plating metal is made to stronglyadhere to the material so that the plated product produced by thisinvention has a superior technical effect in that the thin film of metaltends to not peel off the surface of a material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic front elevation for illustrating the method ofroughening the surface of a material used in one of the conventionalmethods.

FIG. 2 is also a schematic front elevation for illustrating the methodof roughening the surface of a material used in one of the conventionalmethods.]

FIG. 1a is a side cross-sectional view of the surface of a piece ofmaterial, as deformed by a collision of a fine powder particle (incidentat substantially a right angle) therewith in accordance with aconventional method.

FIG. 1b is a side cross-sectional view of the surface of a piece ofmaterial, as deformed by a collision of a fine powder particle (incidentat an acute angle) therewith in accordance with a conventional method.

FIG. 2a is a side cross-sectional view of the surface of a piece ofmaterial, with recesses formed therein in accordance with anotherconventional method.

FIG. 2b is a side cross-sectional view of the surface of the piece ofmaterial of FIG. 2a, after it has been plated with a thin film.

FIG. 3 is a partly-sectional front elevation that illustrates the firstembodiment of this invention.

FIG. 4 is a schematic cross-sectional view of a material forillustrating grooves formed by the first embodiment of this invention.

FIG. 5 is a schematic front elevation for illustrating the secondembodiment of this invention.

FIG. 6 is a schematic front elevation for illustrating the thirdembodiment of this invention.

FIG. 7 is a schematic cross-sectional view for illustrating groovesformed by the third embodiment of this invention.

FIG. 8 is a schematic front elevation for illustrating the fourthembodiment of this invention.

FIG. 9 is a schematic front elevation for illustrating the fifthembodiment of this invention.

FIG. 10 is a schematic cross-sectional view for illustrating grooves andtheir ridge portions formed by the fifth embodiment of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiment 1

Below, we explain, in detail, by referring to FIGS. 3 and 4, anapparatus to be used in a first embodiment that causes a needle topenetrate the surface of a material M, thereby roughening it. As in FIG.3, a moving mechanism 12 is disposed on the lowermost part in the cavityof a column 1 C-shaped in cross-section. On the upper surface of themoving mechanism 12, a material-fixing-mechanism 2, which can fix thematerial M, is disposed. The moving mechanism 12 is adapted to move thematerial-fixing mechanism 2 in a horizontal plane.

A recess-forming mechanism 3 is disposed at a position just above thematerial-fixing-mechanism 2. The recess-forming mechanism 3 comprises aretainer 5, a mounting member 6, a motorized cylinder 7, and a mountingmember 8. The cylinder 7 is mounted on the mounting member 8, which ismounted on the uppermost part within the cavity of the column 1. Theretainer 5 is connected to the lower end of the piston rod of thecylinder 7, and adapted to be moved, through a guide member 6, by theactuation of the cylinder 7.

The retainer 5 can retain the base portions of a. plurality of needlesor drawn wires, each having a diameter of 3˜95 μm, while the needles orwires are inclined at angles of less than 90 degrees, but more than 45degrees, to the surface of the material. In this embodiment, fourneedles 4 are retained by the retainer 5. Two pairs of oppositelyarranged needles are so arranged that each of four needles 4 is disposedat each of four vertexes of one square. Simultaneously, one pair ofneedles 4 are disposed on one of two diagonal lines of the square. Inother words, the one pair of needles 4 are disposed on the diagonal lineof the square such that they are oppositely positioned to each other atrespective vertexes. Therefore, in FIG. 3 one needle 4 is behind theother needle. Thus, only three needles can be seen in FIG. 3. Eachneedle has a diameter of 8 μm, and is inclined at an angle of about 80degrees to the surface of the material. The cylinder 7 can act as ameans for elevating or lowering the retainer 5.

A controller 9, which is adapted for detecting a reaction force againstthe cylinder 7 so as to generate a command to control the descendingforce of the cylinder 7, is electrically connected to it.

By using the thus-constructed apparatus, the surface of the material M,an aluminum plate 10×60×1 (mm), was roughened for use as a platedproduct. The aluminum plate was fixed by the material-fixing mechanism2. Then, the cylinder 7 was actuated so as to have the retainer 5 andthe needles 4 descend, thereby causing the needles 4 to penetrate thesurface of the aluminum plate. Usually, the stiffness of the aluminumplate is lower than that of the needles 4. Therefore, even when the fourneedles 4, inclined in different directions from each other, are urgedto penetrate the plate, the plate suffers the plastic deformation whileallowing the advance of the needles 4. Therefore, the tops of fourneedles 4 can penetrate the aluminum plate. However, each of recessesthus formed is somewhat deformed. Thereafter, the cylinder 7 wasactuated to be retracted so as to have the needles 4 and the retainer 5ascend, so that the needles 4 were withdrawn from the aluminum plate.Thus, a plurality of recesses, each having an anchor, on the surface ofthe aluminum plate, were obtained. Thereafter, the aluminum plate,provided with the recesses, was copper-plated to obtain a desired platedproduct. The aforesaid anchor portion means a hollow (a), i.e., as inFIG. 4, a part that is laterally hollowed out from a line which is drawnfrom the edge of the opening of a recess and that is perpendicular tothe surface of a material.

In this embodiment, the number of penetrating needles per 1 cm² of thesurface of the aluminum plate varies. The number of penetrating needlescorresponds to the number of recesses. Each recess has an opening of 10μm and a depth of 5 μm.

The plated plate was cut into a plurality of test pieces. Thereafter,bilaterally swinging fatigue tests (a repeated flex test) were carriedout by bending each test piece 10,000 times. After each test a thin filmof metal covering the surface of a piece was checked to see if there wasa peeled part. The results are shown in Table 1.

TABLE 1 Method of Roughening the Percentages of Test Pieces Surface of aMaterial Having Peeled Parts Conventional Chemical Etching More than 60%Methods Shot Peening (Surface More than 50% Roughness 55 μm) ShotPeening (Surface More than 40% Roughness 8 μm) This Invention Number ofPenetrating More than 35% Needles (5,000/cm²) Number of Penetrating Lessthan 10% Needles (10,000/cm²) Nurnber of Penetrating Less than 1%Needles (250,000/cm²)

A certain degree of peeling occurred on less than 10% of the total testpieces that had recesses of 10,000/cm², each recess being provided withan anchor. A certain degree of peeling occurred on less than 1% of thetotal test pieces that had recesses of 250,000/cm², each recess beingprovided with an anchor. A certain degree of peeling occurred on morethan 35% of the total test pieces that had recesses of 5,000/cm², eachbeing provided with an anchor. This type of test piece has no utility.

A preferable degree of peeling is less than 30% of the total testpieces. Table 1 shows that many recesses that each had an anchor portionprovided on the surface of the aluminum plate caused a thin film ofmetal to be unlikely to be peeled off the aluminum plate.

Next, control tests by conventional methods, for comparing them with theresults obtained from the first embodiment of this invention, werecarried out. On an aluminum plate as used in the first embodiment, achemical etching test and a shot peening test were carried out. Theresults are shown in Table 1.

As in Table 1, a certain degree of peeling occurred on more than 60% ofthe total test pieces which were roughened by a chemical etching. Also,a certain degree of peeling occurred on more than 50% of the total testpieces subjected to a shot peening and that had a surface roughness of55 μm. Each test piece was roughened by causing shots, each 0.8 mm indiameter, to hit the test piece at a speed of 70 m/sec. Also, a certaindegree of peeling occurred on more than 40% of the total test piecessubjected to a shot peening and that had a surface roughness of 8 μm.Each test piece was roughened by causing shots, each 0.2 mm in diameter,to hit the test piece at a speed of 30 m/sec.

In the first embodiment, the size of the opening of a recess and thedepth of the recess were changed to have different values.

As a result, when the size of the opening of a recess was less than 5μm, the binding power between the molecules of a thin film of metal wasgreater than that between the molecules of the thin film of metal andthe aluminum plate, or was greater than the gravitational forceaffecting them. Therefore, the metal could not enter the recess of thealuminum plate. When the size of the opening of a recess was more than100 μm, the metal was able to enter the recess of the material. However,in that case any part that adhered to the bottom surface of the recessresembled the case where the surface of the material that had no recesswas covered. This led to the same result as in the conventional methods.Also, the adhesion properties were the same as in the conventionalmethods.

When the depth of a recess was less than 20 percent of the size of anopening, no good peeling resistance could be obtained, and theperformance remained the same as that of the conventional methods. Whenthe depth of the recess was more than the size of an opening, energy wasneeded to cause a needle or the like to penetrate the material. However,nevertheless this had no effect.

The size of a needle or drawn wire material to provide a recess that hasan opening of 5 μm was about 3 μm. The size of a needle or drawn wirematerial to provide a recess that has an opening of 100 μm was about 95μm. Therefore, to provide a recess that has an opening ranging from 5 μmto 100 μm, it is preferable to use a needle or drawn wire material thathas a size of 3 μm to 95 μm in diameter.

When the angle of a needle or drawn wire material to the aluminum platewas less than 45 degrees or more than 90 degrees, the adhesion of theplating metal to the aluminum plate was poor.

Embodiment 2

Below, a second embodiment will be explained by referring to FIG. 5. Inthe second embodiment, the material-fixing mechanism 2 and the movingmechanism 12 were the same as those used in the first embodiment.However, in the second embodiment, a recess-forming mechanism 10comprises two pairs of oppositely arranged retainers 5 and their relatedelements. One pair of retainers 5 and their related elements are soarranged that each retainer 5 and its related element of the pair aredisposed at each vertex of one pair of opposing vertexes of one square.Simultaneously, the one pair of retainers 5 and their related elementsare positioned on the diagonal line of the square connecting theopposing vertexes. Therefore, one retainer 5 of the pair and its relatedelements are behind the other retainer 5 and its related elements. Thus,only three retainers 5 and their related elements can be seen in FIG. 5.Each retainer 5 is connected to the lower end of the piston rod of asmall motorized cylinder 11. The retainer 5 is adapted to ascend ordescend through a guide member 6 by the actuation of the cylinder 11.The guide members 6 are mounted, by means of mounting members 8, on theuppermost part within the cavity of the column 1. A single needle 4 isretained by each retainer 5, while each needle is inclined at an angleof about 70 degrees to the surface of the material M. Each needle 4 canindependently ascend or descend by means of each retainer 5, by theactuation of the cylinder 11.

In the second embodiment, the same technical effects as those obtainedin the first embodiment were obtained.

Embodiment 3

Next, we explain, in detail, by referring to FIGS. 6 and 7, an apparatusto be used in a third embodiment that causes razor-like cutting bladesto penetrate the surface of an aluminum plate, to roughen it. As in FIG.6, a moving mechanism 222 is disposed on the lowermost portion withinthe cavity of a C-shaped column 21. A material-fixing mechanism 22 forfixing a material M is disposed over the moving mechanism 222. Themoving mechanism 222 acts as a second moving means and can move thematerial-fixing mechanism 22 in a horizontal plane.

A groove-forming mechanism 23 is disposed at a position just above thematerial-fixing mechanism 22 in the column 21. The groove-formingmechanism 23 comprises a motorized cylinder 27 mounted by means of amounting member 29 on a moving mechanism 28, which acts as a firstmoving means and is mounted on the uppermost part within the cavity ofthe column 21, a guide member 26 disposed below the cylinder 27 andconnected to the lower part of the cylinder 27, and a retainer 25 forretaining three pairs of razor-like cutting blades 24. The retainer 25is connected to the lower end of the piston rod of a motorized cylinder27. The base portions of the blades 24 can be retained by the retainer25, so that each blade can incline to the surface of the material atangles of more than 45 degrees, but less than 90 degrees. In thisembodiment each blade is inclined at an angle of about 60 degrees.

The retainer 25 is adapted to retain a razor-like cutting blade of athickness of from 3 to 95 μm. In this embodiment a razor-like cuttingblade having a thickness of 8 μm was used. The shape of the edge portionof each blade is acute-angled so as to give a cross-sectional shape to agroove in the material, as in FIG. 7. The cylinder 27 acts as a meansfor elevating or lowering the retainer 25 through a guide member 26.Therefore, the retainer 25 can be moved to ascend or descend by theactuation of the cylinder 27. The moving mechanism 28 is adapted to movethe cylinder 27 horizontally so that the retainer 25 is caused to movebackward or forward in the longitudinal direction of the razor-likecutting blade 4.

A controller 20 positioned above the column 21 is electrically connectedto the motorized cylinder 27. The controller 20 acts as a control meansto detect any reaction force against the motorized cylinder 27 so as togenerate a command to control the pressing force of the cutting blades 4on the material M.

By using the thus-constructed apparatus, the surface of the aluminumplate was roughened for use as a plated product. This roughening wasdone before the surface of the aluminum plate to be a plated product wasplated.

First, the plate was fixed to the material-fixing mechanism 22. Then,the motorized cylinder 27 was actuated to extend so as to have thecutting blades 24, the retainer 25, and so forth, descend, under thecontrol of the controller 20. This caused the cutting blades 24 topenetrate the surface of the plate in a desired depth. Thereafter, thecutting blades 24, the motorized cylinder 27, and so forth, were movedby the moving mechanism 28 in the longitudinal directions of the cuttingblades 24 so that the surface of the plate was cut to form groovesthereon. When the, cutting blades 24 were moved a predetermineddistance, the motorized cylinder 27 was actuated to retract, to have theretainer means 25 and so forth ascend, thereby withdrawing the cuttingblades 24 from the surface of the plate. Then, the plate was moved bythe moving mechanism 222 in a predetermined direction.

By repeating this operation, many grooves on the aluminum plate wereobtained that inclined to the surface of the surface of the plate at anangle of about 60 degrees. When the angle of a razor-like cutting bladeto the aluminum plate was less than 45 degrees or more than 90 degrees,the adhesion of the plating metal to the aluminum plate was not good.

The pattern on the surface of the plate was in a lattice form. However,the pattern may be in a diamond form.

After this operation, the surface of the plate, provided with manygrooves, was plated to obtain a plated product.

The cross-sectional shape of the groove obtained in this embodiment canbe seen in FIG. 7. It had an anchor portion, which means a hollow (a),i.e., a part that is laterally hollowed out from a line which is drawnfrom the edge of the opening of the groove and that is perpendicular tothe surface of the aluminum plate.

In this embodiment, 20 grooves per 1 cm were obtained. The size of theopening of each groove was 10 μm and the depth of it was 5 μm.

Then, the aluminum plate was copper-plated to make a test piece. Theplated plate was cut into a plurality of test pieces.

Thereafter, bilaterally swinging fatigue tests (a repeated flex test)were carried out 10,000 times on each piece. After each test a thin filmof metal covering the surface of a piece was checked to see if anypeeled part was observable. The results are shown in Table 2.

TABLE 2 Percentages of Test Method of Roughening the Pieces HavingPeeled Surface of a Material Parts Conventional Chemical Etching Morethan 60% Methods Shot Peening (Surface More than 50% Roughness 55 μm)Shot Peening (Surface More than 40% Roughness 8 μm) This InventionCutting by Razor-Like Cutting Less than 5% Blades (Opening: 10 μm,Depth: 5 μm, Lattice Lines: 20/cm)

Since a part of the thin film of metal entered the anchor portions ofthe grooves, the plated product had been provided with the desiredpeeling resistance.

A certain degree of peeling occurred on less than 5% of the total testpieces prepared by this invention. Table 2 shows that a plurality ofgrooves, each groove being provided with an anchor portion as in FIG. 7,provided on the surface of a material, caused the thin film of platedmetal hardly to peel off. The pattern provided on the surface of thematerial by those grooves that had an anchor portion may be in a latticeform or in a diamond form. They do not prevent the grooves fromfunctioning as anchor portions. However, it is preferable that any twoadjoining grooves be arranged not in parallel.

Next, control tests by conventional methods, for comparing them with theresults obtained from the first embodiment of this invention, werecarried out. On an aluminum plate as used in the third embodiment, achemical etching test and a shot peening test were carried out. Theresults are shown in Table 2.

As in Table 2, a certain degree of peeling occurred on more than 60% ofthe total test pieces which were roughened by a chemical etching. Also,a certain degree of peeling occurred on more than 50% of the total testpieces that had a surface roughness of 55 μm. Each test piece wasroughened by causing shots, each 0.8 mm in diameter, to hit the testpiece at a speed of 70 m/sec. Also, a certain degree of peeling occurredon more than 40% of the total test pieces that had a surface roughnessof 8 μm. Each test piece was roughened by causing shots, each 0.2 mm indiameter, to hit the test piece at a speed of 30 m/sec.

In this embodiment, when the width of the opening of a groove was lessthan 5 μm, the binding power between the molecules of a thin film ofmetal was greater than that between the molecules of the thin film ofmetal and the aluminum plate, or was greater than the gravitationalforce affecting them. Therefore, the metal could not enter the groove ofthe aluminum plate. When the width of the opening of a groove was morethan 100 μm, the metal was able to enter the groove of the aluminumplate. However, in that case no part that adhered to the groove did soeffectively function as in a groove that has an anchor portion. Thisresembled the case where the surface of the aluminum plate that had nogroove is covered. This led to the same result as in the conventionalmethods. Also, the adhesion properties were the same as in theconventional methods.

The thickness of a razor-like cutting blade to provide a groove that hasa width of an opening of 5 μm was about 3 μm. The thickness of therazor-like cutting blade to provide a groove that has a width of anopening of 100 μm was about 95 μm. Therefore, to provide a groove thathas a width of an opening ranging from 5 μm to 100 μm, it is preferableto use a razor-like cutting blade that has a thickness of 3 μm to 95 μm.

When the depth of a groove was less than 20 percent of the width of theopening of the groove, the peeling resistance could not be improved, andthe performance remained the same as in the conventional methods. Whenthe depth of the groove was more than the width of an opening, energywas needed to cause a cutting blade to penetrate the material. However,nevertheless this had no such a good effect as a groove that has ananchor portion.

Embodiment 4

Below is a fourth embodiment of this invention. In this embodiment, asin FIG. 8, a single-blade construction was used. In it a groove-formingmechanism 23 comprises two set of retainers 25 and their relatedelements. Each cutting blade 24 is retained by each retainer 25, eachbeing adapted to ascend or descend by the actuation of each motorizedcylinder 27. Each cylinder 27 is mounted by means of a mounting member28 on the uppermost part within the cavity of a C-shaped column 21.

Each cutting blade 24 can independently ascend or descend. In this casethe pattern formed by grooves on the surface of the material was zigzag.The cutting blade was of a razor-like form. However, it is not limitedto that form, if it has a high stiffness. For instance, a band-platehaving a narrow width can be used. In this embodiment, each blade 24 wasarranged to incline at an angle of about 80 degrees. However, thegroove-forming mechanism 23 can be arranged so that each blade 24 isinclined at angles in a range from 45 degrees to 90 degrees to thesurface of the material. As a means for elevating or lowering theretainer, the motorized cylinder 27 was used in this embodiment.However, it is not limited to a motorized cylinder. For instance, ahydraulic cylinder can be used.

Embodiment 5

Below is a fifth embodiment of this invention. In this embodiment, as inFIG. 9, an apparatus to form grooves and ridges on the surface of analuminum plate 10×60×1 (mm) is provided. In it a rotary-disk cuttingblade 31 can be rotated and horizontally moved on the surface of thealuminum plate while the blade is pressed against the surface, toroughen it.

The apparatus comprises a groove-forming mechanism 36, a material-fixingmechanism 33, and a moving means 37. The moving means 37 acts as asecond moving means. The groove-forming mechanism 36 comprises a movingmechanism 35, which acts as a first moving means, a retainer 32 toretain a pneumatic motor 38 via a universal coupling 345, a motorizedcylinder 34 to have the retainer 32 ascend or descend, a guide member344, and a horizontally-moving mechanism 41 mounted on the uppermostpart within the cavity of a C-shaped column 39. The motorized cylinder34 is mounted on the moving mechanism 35, which is mounted on thehorizontally-moving mechanism 41. To the lower end of the piston rod ofthe motorized cylinder 34, the retainer 32 is connected. The retainer 32can be moved up or down within the guide member 344. The rotary-disccutting blade 31 has a diameter of 20 mm and a thickness of 8 μm.

The rotary-disk cutting blade 31 is rotatably mounted on the lower endof the pneumatic motor 38. By the universal coupling 345, the pneumaticmotor 38 and the blade 31 can incline to the surface of the aluminumplate, at angles from 30 to 150 degrees. In this embodiment the surfaceof the blade 31 was inclined at an angle of about 60 degrees. The movingmeans 35 is adapted to move the motorized cylinder 34 and the retainer32 in the direction that the blade of the rotary-disk cutting blade isdirected. The moving mechanism 37 is adapted to horizontally move thematerial-fixing means 33. The horizontally-moving mechanism 41 isadapted to horizontally move the cylinder 34 and its related parts.

Above the column 39, a controller 30 is disposed. It is electricallyconnected to the motorized cylinder 34, and acts as a control means. Itcan detect a reaction force against the cylinder 4 so as to generate acommand to control the pressing force of the rotary-disc blade 31 on thealuminum plate.

Below is explained the method of roughening the surface of the aluminumplate, using the thus-constructed apparatus. This roughening was donebefore the surface of the aluminum plate was plated to form a platedproduct.

First, the aluminum plate was fixed to the material-fixing means 33.Then, compressed air was supplied to the pneumatic motor 38 to rotatethe rotary-disk cutting blade 31. Thereafter, the motorized cylinder 34was actuated to have its piston rod extend so as to have the rotary-diskcutting blade 31, the air motor 38, the retainer 32, and so forth,descend, under the control of the controller 30. This caused therotary-disk cutting blade 31 to press the surface of the aluminum plateby a force of a specified degree. Then, the rotary-disk cutting blade31, the air motor 8, and so forth, were moved by the moving mechanism 35in the direction that the rotary-disk cutting blade 31 was rotated.Thus, the surface of the aluminum plate was cut to form grooves thereon.

When the cutting blade 31 was moved a predetermined distance, themotorized cylinder 34 was actuated to retract, to have the retainer 32and so forth ascend, thereby separating the rotary-disk cutting blade 31from the aluminum plate. Then, the aluminum plate was moved by themoving mechanism 37 in a predetermined direction. If desired, theretainer 32, the rotary-disk cutting blade 31, and so forth, can behorizontally rotated by the horizontally-moving mechanism 41. Thus, themovements of the rotary-disk cutting blade 31 caused the aluminum plateto be cut to form grooves.

Simultaneously with the cutting of grooves, as in FIG. 10, a part of thealuminum plate was raised by the rotary-disk cutting blade 31 to formridge portions (n) at both edges of the opening of the groove.

By repeating this operation, many grooves were formed that inclined tothe surface of the aluminum plate at an angle of about 60 degrees.Further, ridge portions were formed along the edges of the openings ofthe grooves. The pattern by the grooves on the surface of the materialwas in a lattice form. However, the pattern may be in a diamond form.

After the operation, the surface of the aluminum plate, provided withmany grooves and ridge portions, was plated to obtain a plated product.Since a part of the thin film of metal entered each groove so that theanchor portion strongly grasped the metal entered therein, the platedproduct was provided with the desired peeling resistance.

The aforesaid anchor portion means a hollow (a), i.e., as in FIG. 10, apart that is laterally hollowed out from a line which is drawn from theedge of the opening of a groove and that is perpendicular to the surfaceof the aluminum plate. Also, (b) denotes the depth of a groove, and (c)denotes the height of the ridge portion of the groove.

When the angle of the rotary-disk cutting blade to the surface of thealuminum plate was less than 30 degrees, the adhesion of the platingmetal to the aluminum plate was poor. When the angle of the rotary-diskcutting blade to the surface the aluminum plate was more than 150degrees, the adhesion of the plating metal to the aluminum plate wasalso poor. Therefore, preferably the angle of the cutting blade to thesurface of a material ranges from 30 to 150 degrees. The cross-sectionalshape of the groove obtained in this embodiment can be seen in FIG. 10.The width of the opening of the groove was 10 μm, the depth of it was 8μm, and the height of the ridge portion was 4 μm. There were 20 groovesper 1 cm. The pattern of the grooves on the aluminum plate was in alattice form.

After the cutting operation, the aluminum plate was copper-plated tomake test pieces.

Then, bilaterally swinging fatigue tests (a repeated flex test) werecarried out 10,000 times on each piece. After each test a thin film ofmetal covering the surface of a piece was checked to see if any peeledpart was observable. The results are shown in Table 3.

TABLE 3 Percentages of Test Method of Roughening Pieces Having Peeledthe Surface of a Material Parts Conventional Methods Chemical EtchingMore than 65% Shot Peening (Surface More than 55% Roughness 60 μm) ShotPeening (Surface More than 45% Roughness 120 μm) This Invention Cuttingby Rotary-Disk Less than 5% Cutting Blades (Depth: 8 μm, Height: 4 μm,Lattice lines: 20/cm)

A certain degree of peeling occurred on less than 5% of the total testpieces prepared by this invention. Table 1 shows that a plurality ofgrooves, each groove being provided with anchor portions (n) as in FIG.10, provided on the surface of a material, caused the thin film of metalto hardly peel off. When the groove and its ridge portion were made tobe in a curved form, or in a different combined form, the same resultswere obtained. Also, when the depth of the groove and the height of theridge portion of the groove were changed within a predetermined range,the same results were obtained.

As in Table 3, a certain degree of peeling occurred on more than 65% ofthe total test pieces which were roughened by a chemical etching. Also,a certain degree of peeling occurred on more than 55% of the total testpieces that had a surface roughness of 60 μm. Each test piece wasroughened by peening, with each shot being 0.8 mm in diameter, to hitthe test piece at a speed of 70 m/sec. Also, a certain degree of peelingoccurred on more than 45% of the total test pieces that had a surfaceroughness of 12 μm. Each test piece was roughened by causing shots, each0.2 mm in diameter, to hit the test piece at a speed of 30 m/sec.

In this embodiment, when the width of the opening of a groove is lessthan 5 μm, the binding power between the molecules of a thin film ofmetal is greater than that between the molecules of the thin film ofmetal and the material, or is greater than the gravitational forceaffecting them. Therefore, the metal cannot enter the groove of thealuminum plate. When the width of the opening of a groove is more than100 μm, the metal can enter the groove of the material. However, in thatcase any part that adheres to the groove does not so effectivelyfunction as a groove that has an anchor portion. This resembles the casewhere the surface of the aluminum plate that has no groove is covered.This leads to the same result as in the conventional methods. Also, theadhesion properties are the same as in the conventional methods.

The thickness of a rotary-disc cutting blade to provide a groove thathas the width of the opening of a groove of 5 μm was about 3 μm. Thethickness of the rotary-disc cutting blade to provide a groove that hasthe width of the opening of a groove of 100 μm was about 95 μm.Therefore, to provide a groove that has the width of the opening of agroove ranging from 5 μm to 100 μm, it is preferable to use arotary-disc cutting blade that has a thickness of 3 μm to 95 μm.

When the depth of a groove and the height of the ridge portion of thegroove are less than 10 percent of the thickness of a plated layer,especially the shearing force at the contact area of the plating isweakened. This results in fewer anchor effects. When the depth of thegroove and the height of the ridge portion of the groove are more thanthe thickness of the plated layer, the metal can enter the groove.Therefore, preferably the depth of a groove and the height of the ridgeportion of the groove are less than 90 percent of the thickness of aplated layer.

However, when the thickness of the plated layer at a portion where theridge portion of a groove is located is high, the plated layer becomesuneven. Also, the binding power between the metal and the aluminum plateat that portion is weak.

Therefore, the plating metal that adheres to the groove has less effectto function as in a groove that has an anchor portion. This results in aplated layer that tends to be easily broken.

Generally, the thickness of a plated layer ranges from 10 to 20 μm. Toobtain a good plated layer, the depth of a groove and the angle of thegroove to the surface of a material should range from 2 to 18 μm, andfrom 30 to 150 degrees, respectively, and the height of the ridgeportion of the groove should range from 2 to 18 microns.

The pattern provided on the surface of the aluminum plate by the groovesand their ridge portions was in a lattice form. However, it may be in adiamond form. Neither prevents the grooves or their ridge portions fromfunctioning as anchor portions. However, it is preferable that any twoadjoining grooves be arranged not in parallel in the cross section ofthe aluminum plate.

The grooves and their ridge portions can be linear or curved, or in acombined form. The depth of a groove and the height of the ridge of thegroove can be varied within a predetermined range.

Further, the height of the ridge portion of a groove is preferably lowerthan the depth of the groove. As a means to form a groove and its ridgeportion, any cutting blade that has a stiffness of a certain degree canbe used. For instance, a razor-like blade, a band-plate having a narrowwidth, or a rotary-disk cutting blade having a desired thickness anddiameter, can be preferably used. This cutting blade is caused to bepressed with a desired pressure against the surface of a material whilethe blade is moved, so that the surface of the material is cut orcarved.

In the above embodiment, the rotary-disk cutting blade 31 was rotated bythe pneumatic motor 38. However, in place of it, an electric motor canbe used to rotate it. It will cause the same operation and effects asthose caused by the pneumatic motor 38.

Also, the motorized cylinder 34 was used as an elevating or loweringmeans. However, the means is not limited to a motorized cylinder. Forinstance, a hydraulic cylinder can be used.

As will be understood from the above explanation, by the fifthembodiment of this invention a plurality of grooves are formed on thesurface of a material. The width of the opening of each groove is 5˜100μm and the depth of each groove is 10˜90% of the thickness T of a platedlayer. The angle of each groove to the surface of the material is withina range of more than 30 degrees, but less than 150 degrees. Each grooveis provided at each of both edges of its opening with a ridge portion,the height of which is 10˜90% of the thickness T of the plated layer. Apart of the thin film of metal enters the anchor portion of the groove.Therefore, the thin film of metal hardly peels off the surface of thematerial, as compared with the conventional plated products.

Thus, this invention provides a plated product comprising a material ofwhich the surface has many recesses or grooves that have anchorportions. Therefore, a part of a plating metal enters the anchorportions of the recesses or grooves. Since the anchor portions firmlygrasp the plating metal entered, the plated metal of the product resiststhe force applied in a direction at substantially right angles, so as toprevent the plated metal from peeling off. Also, each of the grooves onthe surface of the material can be provided with a ridge portion at eachof both edges of its opening. Therefore, the plated metal that coversthe grooves and ridge portions of the material also resists the forceapplied in a direction substantially parallel to the surface of thematerial so as to prevent the plated metal from peeling off. Therefore,the plated product produced by this invention has a superior technicaleffect in that the thin film of metal tends to not peel off the surfaceof a material.

What is claimed is:
 1. A method of producing a plated product in which asurface of a metallic or nonmetallic material is plated, comprisingcausing the tip of a needle or a drawn wire material of a diameter of3˜95 μm to penetrate said surface of said material at an angle of lessthan 90 degrees, but more than 45 degrees, withdrawing said needle orsaid drawn wire material from said material and repeating this processso as to provide at said surface of said material many recesses, eachhaving an opening of a diameter of 5˜100 μm and a depth of 0.2 d˜d μm,where d is the diameter of the opening in units of μm, and having ananchor portion, and covering said surface of said material that includessaid recesses with a film of metal.
 2. The method of claim 1, in whichthe number of said recesses are 10⁶/d²˜10⁸/4 d² per 1 cm², where d isthe diameter of the opening in units of μm.
 3. A method of producing aplated product in which a surface of a metallic or nonmetallic materialis plated, comprising causing a cutting blade having a thickness of 3˜95μm to penetrate said surface of said material while said cutting bladeis inclined to said surface of said material at an angle within a rangeof more than 45 degrees, but less than 90 degrees, moving said cuttingblade or said material to cause them to move relative to each other, andrepeating this process so as to provide at said surface of said materiala plurality of grooves, many running in different directions, the widthof the opening of each groove being 5˜100 μm and the depth of eachgroove being 0.2 b˜b (b: said width of the opening, μm), and coveringsaid surface of said material that includes said grooves with a film ofmetal.
 4. A method of producing a plated product in which the surface ofa metallic or nonmetallic material is plated to provide said materialwith a platerd layer having thickness T, said method comprising causinga cutting blade having a thickness of 3˜95 μm to be pressed on saidsurface of said material while said cutting blade is inclined to saidsurface of said material at an angle in a range of more than 30 degrees,but less than 150 degrees, and moving said cutting blade or saidmaterial to cause them to move relative to each other, and repeatingthis process so as to provide at said surface of said material manygrooves, many running in different directions, the width of the openingof each groove being 5˜100 μm, and the depth of each groove being 10˜90%of the thickness T of the plated layer or being 2˜8 μm, and to provideridge portions, the height of each of which is 10˜90% of the thickness Tof the plated layer or 2˜18 μm, and covering said surface of saidmaterial that includes said grooves and ridge portions by metal platingto provide said plated layer.
 5. The method of claim 4, in which saidcutting blade or said material is moved linearly or curvilinearly, or ina combined movement.
 6. The method of claim 4, in which said depth ofsaid groove and said height of said ridge portion are changed bychanging the pressing force of said cutting blade within a predeterminedrange.